package com.hmdp.service.impl;

import cn.hutool.core.bean.BeanUtil;
import cn.hutool.core.bean.copier.CopyOptions;
import cn.hutool.core.lang.UUID;
import cn.hutool.core.util.RandomUtil;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.dto.LoginFormDTO;
import com.hmdp.dto.Result;
import com.hmdp.dto.UserDTO;
import com.hmdp.entity.User;
import com.hmdp.mapper.UserMapper;
import com.hmdp.service.IUserService;
import com.hmdp.utils.RedisConstants;
import com.hmdp.utils.RegexUtils;
import com.hmdp.utils.SystemConstants;
import com.hmdp.utils.UserHolder;
import lombok.extern.slf4j.Slf4j;
import org.springframework.data.redis.connection.BitFieldSubCommands;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.TimeUnit;

/**
 * <p>
 * 服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Slf4j
@Service
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements IUserService {

    @Resource
    private StringRedisTemplate stringRedisTemplate;

    @Override
    public Result sendCode(String phone, HttpSession session) {
        // 1.校验手机号
        if (RegexUtils.isPhoneInvalid(phone)){
            return Result.fail("手机号格式错误!");
        }
        // 2.生成验证码
        String code = RandomUtil.randomNumbers(6);
        // 3.保存验证码到redis
        stringRedisTemplate.opsForValue().set(RedisConstants.LOGIN_CODE_KEY + phone, code,
                RedisConstants.LOGIN_CODE_TTL, TimeUnit.MINUTES);
        // 4.发送验证码
        log.debug("发送短信验证码成功，验证码: {}", code);

        return Result.ok();
    }

    @Override
    public Result login(LoginFormDTO loginForm) {
        // 1.校验手机号
        String phone = loginForm.getPhone();
        if (RegexUtils.isPhoneInvalid(phone)){
            return Result.fail("手机号格式错误!");
        }
        // 2.从Redis获取并校验验证码
        String cacheCode = stringRedisTemplate.opsForValue().get(RedisConstants.LOGIN_CODE_KEY + phone);
        String code = loginForm.getCode();
        if (null == cacheCode || !cacheCode.equals(code)){
            return Result.fail("验证码错误");
        }
        // 3.根据手机号查询用户
        User user = query().eq("phone", phone).one();
        // 4.判断是否存在
        if (null == user){
            // 5.创建新用户
            user = createUserWithPhone(phone);
        }
        // 6. 保存用户信息到Redis
        // 6.1 随机生成token
        String token = UUID.randomUUID().toString(true);
        // 6.2 将User对象转为HashMap存储
        UserDTO userDTO = BeanUtil.copyProperties(user, UserDTO.class);
        // Long转为String
        Map<String, Object> userMap = BeanUtil.beanToMap(userDTO, new HashMap<>(1),
                CopyOptions.create()
                        .setIgnoreNullValue(true)
                        .setFieldValueEditor((name, value)-> value.toString()));
        // 6.3存储
        String tokenKey = RedisConstants.LOGIN_USER_KEY + token;
        stringRedisTemplate.opsForHash().putAll(tokenKey, userMap);
        stringRedisTemplate.expire(tokenKey, RedisConstants.LOGIN_USER_TTL, TimeUnit.MINUTES);
        log.info("用户登陆成功: {}", user.getPhone());
        // 7.返回token
        log.info("返回信息: {}", Result.ok(token));
        return Result.ok(token);
    }

    @Override
    public Result logout(HttpServletRequest request) {
        String token = request.getHeader(SystemConstants.AUTHORIZATION);
        stringRedisTemplate.delete(RedisConstants.LOGIN_USER_KEY + token);
        log.info("用户退出登录: {}", UserHolder.getUser().getId());
        return Result.ok();
    }

    /**
     * 用户签到功能
     *
     * @return R
     */
    @Override
    public Result sign() {
        // 1.获取当前登录用户
        Long userId = UserHolder.getUser().getId();
        // 2.获取日期
        LocalDateTime now = LocalDateTime.now();
        // 3.拼接key
        String keySuffix = now.format(DateTimeFormatter.ofPattern(":yyyyMM"));
        String key = RedisConstants.USER_SIGN_KEY + userId + keySuffix;
        // 4.获取今天是本月的第几天
        int dayOfMonth = now.getDayOfMonth();
        // 5.写入Redis
        stringRedisTemplate.opsForValue().setBit(key, dayOfMonth - 1, true);
        return Result.ok();
    }

    /**
     * 统计本月连续签到天数
     *
     * @return R
     */
    @Override
    public Result signCount() {
        // 1.获取当前登录用户
        Long userId = UserHolder.getUser().getId();
        // 2.获取日期
        LocalDateTime now = LocalDateTime.now();
        // 3.拼接key
        String keySuffix = now.format(DateTimeFormatter.ofPattern(":yyyyMM"));
        String key = RedisConstants.USER_SIGN_KEY + userId + keySuffix;
        // 4.获取今天是本月的第几天
        int dayOfMonth = now.getDayOfMonth();
        // 5.获取本月今天为止的所有签到记录，返回的是10进制数字 BITFIELD sign:1010:202302 get u4 0
        List<Long> result = stringRedisTemplate.opsForValue().bitField(key,
                BitFieldSubCommands.create()
                        .get(BitFieldSubCommands.BitFieldType.unsigned(dayOfMonth)).valueAt(0));
        if (result == null || result.isEmpty()){
            return Result.ok(0);
        }
        Long num = result.get(0);
        if (num == null || num == 0){
            return Result.ok(0);
        }
        // 6.循环遍历
        int count = 0;
        // 6.1数字与1作与运算，得到数字的最后一个bit位
        // 为零说明未签到，结束;不为零，说明已签到，计数器加一
        while ((num & 1) != 0) {
            count++;
            // 把数字右移一位
            num >>>= 1;
        }
        return Result.ok(count);
    }

    private User createUserWithPhone(String phone) {
        User user = new User();
        user.setPhone(phone);
        user.setNickName(SystemConstants.USER_NICK_NAME_PREFIX + RandomUtil.randomString(10));
        save(user);
        return user;
    }
}
